库欣综合征55例临床分析

Clinical analysis of 55 cases with cushing＇s syndrome

目的分析库欣综合征患者的病因分类，各种主要临床表现的出现频率以及实验室检查特点，并对各种诊断方法的效率进行评价。方法收集2003～2008年在我院住院经临床和病理确诊为库欣综合征患者的病例资料，对它们进行回顾性分析。结果在本组病例中，库欣病最多见，肾上腺皮质腺瘤次之。临床表现方面，向心性肥胖和高血压出现的频率最高，均在70％以上。血糖异常和血脂异常的发生率分别为51．43％和70．59％，其中糖尿病的比例高达37．14％。四成以上的患者存在低血钾，肾上腺皮质腺癌患者100％有低血钾，且是重度低血钾。在库欣综合征诊断试验中，敏感性从高到低依次为不被小剂量地塞米松抑制，血皮质醇昼夜节律消失，24小时尿游离皮质醇增高，清晨血皮质醇增高。在库欣综合征患者的鉴别诊断中，80％以上的库欣病患者能被大剂量地塞米松抑制，而几乎94％的肾上腺皮质腺瘤患者不能被大剂量地塞米松抑制。有关影像学检查，垂体MRI可以检测出90％以上的库欣病患者存在垂体腺瘤，而肾上腺CT几乎100％可以发现出肾上腺肿瘤。结论本研究中库欣病和肾上腺皮质腺瘤仍然是最常见的病因，但后者的的比例相对较高。而在临床特点方面，高血压和糖尿病的发生率较高。对于库欣综合征的诊断和鉴别诊断，目前没有一种检查方法具有100％的敏感性，我们应对各种结果作出综合判断。

Objective To analyze the etiopathogenesis, the prevalence of signs and laboratory characteristics with Cushing＇s syndrome, to evaluate the efficiencies of various assays in diagnosis and differential diagnosis. Methods We collected the clinical data of 55 eases with Cushing＇ s syndrome admit- ted to our hospital from 2003 to 2008, then reviewed them retrospectively. Results Cushing＇ s disease is the most common cause of Cushing＇ s syndrome, the secondary cause is adrenal adenoma. Central obesity and hypertension are the most frequent signs,which account for more than 70% patients. The prevalence of dysglyeemia and dyslipidemia are 51.43 % and 70.59% , respectively, but the ratio of frank diabetes is as high as 37.14%. More than 40% patients have hypokalemia. Furthermore, all the patients with adrenal carcinoma have severe hypokalemia. In the screening tests, for diagnosis of Cushing＇ s syndrome,the sensitivity from high to low is lack of eortisol suppression after low dose dexamethasone suppression test ,loss of normal circadian rhythm of plasma eortisol, increased 24 h urinary free eortisol, elevated morning plasma cortisol. And in the differential diagnosis, more than 80% patients with Cushing＇s disease can be suppressed by high dose dexamethasone suppression test,but almost 94% patients with adrenal adenoma can not be suppressed. With regard to imaging examination, MRI of the pituitary exhibits a sensitivity of more than 90% in identifying a pituitary adenoma,but CT of the adrenal glands can almost detect 100% adrenal neoplasm. Conclusions In our cases, Cushing＇ s disease and adrenal adenoma are also the most common causes,but the ratio of the latter is relative higher than ever reported. Hypertension and diabetes are also higher than previous reported. There is no test with 100% sensitivity for diagnosis and differential diagnosis of Cushing＇s syndrome,which need integrative analysis of different kinds of tests.